Sure looks like a Cadillac to me. Aluminum and with no heat p***age, could be an early Cal Connell Detroit Racing Equipment part or even more likely a Cal Connell Crusader Marine part. See attached 57 Eldo cast iron part (with heat p***age).
I know this thread is 5 years old but did you positively ID this intake? The reason I ask is that I picked up an identical aluminum intake. The only id numbers were 2000-1. It is painted aluminium. I thought it was a Caddy intake and the seller thought the same.